ETF Trends CEO Tom Lydon discussed the SPDR S&P 500 ETF Trust (SPY) vs Invesco S&P 500 Equal Weight ETF (RSP) on this week’s “ETF of the Week” podcast with Chuck Jaffe on the MoneyLife Show.

SPY is one of the largest and most heavily-traded ETFs in the world, offering exposure to one of the most well known equity benchmarks. While SPY certainly may have appeal to investors seeking to build a long-term portfolio and include large cap U.S. stocks, this fund has become extremely popular with more active traders as a way to toggle between risky and safe assets. A look at SPY's daily turnover reveals the short average holding period and the popularity with active traders.

RSP is linked to the S&P 500 Index, however its unique weighting methodology will make it useful for some, while impractical for active traders. Like many Rydex products, RSP is linked to an equal-weighted index, meaning that component companies receive approximately equal allocations. That results in exposure that is considerably more balanced than other alternatives such as SPY, and a methodology that some investors believe will add value over the long haul. In return for this unique exposure you can expect higher fees; this ETF is considerably more expensive and less liquid than both SPY and IVV, though it is still extremely cost efficient compared to most mutual funds.